mkcert is a command-line tool written in Go that simplifies the creation of locally-trusted development certificates. It eliminates the need for complex certificate management by automatically creating and installing a local certificate authority into the system root store, then generating certificates for any domain names specified by the user. The tool addresses a common development problem: while self-signed certificates cause trust errors in browsers, obtaining real certificates from certificate authorities for local development domains like localhost or example.test is impractical or impossible. mkcert solves this by managing a local CA that the operating system trusts.
The tool requires no configuration to get started. Users simply specify the domain names they want certificates for, and mkcert handles certificate generation and installation automatically. It supports installation across multiple platforms including macOS, Linux, and Windows, with platform-specific installation methods documented for each. On macOS, installation is available through Homebrew or MacPorts. Linux users can install via Homebrew on Linux, build from source, or use pre-built binaries, with Arch Linux users having access to an official repository package. Windows users can install through Chocolatey, Scoop, or pre-built binaries.
The repository demonstrates active maintenance and community engagement. GitGenius tracking shows that across 59 issues and pull requests, the median response latency is 57.3 hours, indicating relatively prompt attention to user inquiries. The most frequently tagged issues involve questions, requests for additional information, and help wanted items. FiloSottile, the repository owner, has been the primary contributor with 54 tracked events, while other contributors like rfay and adamdecaf have also been active in triaging and development.
mkcert supports installation into multiple root certificate stores across different systems and applications. It can install certificates into the macOS system store, Windows system store, and various Linux distributions using their respective certificate management tools. The tool also supports Firefox, Chrome, Chromium, and Java keystores. Users can selectively install into specific trust stores using the TRUST_STORES environment variable.
The tool includes several advanced features beyond basic certificate generation. It automatically generates S/MIME certificates when email addresses are included in the certificate names. For mobile device support, mkcert provides the root CA certificate that can be installed on iOS and Android devices, with detailed instructions for each platform. The tool also addresses Node.js compatibility by documenting the NODE_EXTRA_CA_CERTS environment variable, since Node does not use the system root store by default.
The repository is classified across multiple security and development categories including certificate generation, local development, SSL, TLS, HTTPS, trusted certificates, CA management, self-signed certificates, and security automation. The tool's relevance to broader development ecosystems is reflected in GitGenius's identification of overlapping contributors with major repositories including microsoft/vscode, microsoft/typescript, and rust-lang/rust, suggesting the tool is used across diverse development communities.
